A California state senator who introduced a bill to tighten the state's gun control has received a flood of racist calls and letters in response.

With Senate Bill 249, Sen. Leland Yee (D-San Francisco) is trying to close a loophole in one of the California gun control laws, which already includes some of the toughest restrictions in the nation.

It is currently illegal in California for manufacturers to sell certain guns with detachable magazines, or the storage areas that allow for repeat firing. To get around the law, manufacturers have been selling guns with tools, or conversion kits, that allow one to reload in seconds. Yee's bill seeks to ban such devices, including “bullet buttons” and "mag magnets."

“While most gun owners are law-abiding, it is a fact that such weapons are more likely to be used to kill an innocent person than used in self-defense," Yee said in a press release. "One only needs to look at England, Japan, and other nations with strict gun access to see that these types of gun control laws are effective in preventing gun-related homicides.”

The move comes after recent mass shootings in Aurora, Colo., and Milwaukee. The alleged shooter in Aurora used an AR-15, which is legal with a conversion kit in California, although the 100-round magazine he used is not.

"No one will convince me it's anything other than a joke to say that having multiple clips and semi-automatic weapons that can shoot 100 or more bullets at a time is necessary in this state or in this country. It's ridiculous," Senate President Pro Tem Darrell Steinberg, who is a co-author, told the Sacramento Bee.

"I know that everyone is afraid of the strong lobby on the other side," he continued, adding that lawmakers "can't be afraid to do what is just plain common sense."

In response, gun rights activists have flooded Yee with racist calls and comments, about 99 percent of which are from outside the San Francisco district, according to Yee's office. Others -- via Twitter, Facebook, Calguns.net, AR15.com, AroundTheCapitol.com and other sites -- have posted offensive photos and comments, including racist caricatures of Asians and comments such as “Take this sh*t back to China you communist f*ck,” “who the f*ck let a ch*nk into office,” and “Read the AMERICAN constitution, you commie ch*nk f*ck,” among others. Yee was born in China and came to the U.S. when he was three.

The California Association of Federal Firearms Licensees paid for a billboard on the 101 North freeway in San Carlos that reads “Sen. Yee hates your civil rights! Stop SB 249,” the Daily Journal reports. A few sites are selling T-shirts and mugs against the bill, including a shirt that reads "No Yee Can't."

Scott Jackson, chief instructor for the Bay Area Firearms Training Group, told Patch that blaming guns for mass killings is akin to blaming cars for vehicle accidents.

He said that psychoactive drugs -- not guns -- cause massacres. “Every horrific crime is because people are on anti-depressants and psychoactive drugs," he said, adding that both the suspects in the recent Colorado and Wisconsin shootings took such medications.

Jackson said that if civilians were allowed to carry concealed weapons, they would be able to take out shooters and save innocent lives.

The National Rifle Association calls the bill a "gun ban monster" on its website and encourages members to write California legislators expressing their opposition. "Thousands of owners could be arrested for inadvertent violations," the website reads. "If you own an affected firearm, your only choices would be to destroy it, surrender it to a law enforcement agency, sell it out of state or have it confiscated at the time of your arrest!"

California Attorney General Kamala Harris supports SB 249, and legislators who have signed on as co-authors include Sen. Kevin de León (D-Los Angeles), Sen. Loni Hancock (D-Berkeley), Sen. Ted Lieu (D-Torrence), Assemblyman Anthony Portantino (D-La Cañada Flintridge), Assemblyman Mike Feuer (D-Los Angeles) and Senate President Pro Tem Darrell Steinberg (D-Sacramento), according to Yee's office.

The bill was approved last month by the Assembly Public Safety Committee and will be considered by the Assembly Appropriations Committee next week.

Earlier on HuffPost:

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  • 1981: The Attempted Assassination Of President Ronald Reagan

    on March 30, 1981, President Reagan and three others were shot and wounded in an assassination attempt by John Hinckley, Jr. outside the Washington Hilton Hotel in Washington, D.C. Reagan's press secretary, Jim Brady, was shot in the head.

  • 1993: The Brady Handgun Violence Act

    The Brady Handgun Violence Act of 1993, signed into law by President Bill Clinton, mandated that federally licensed dealers complete comprehensive background checks on individuals before selling them a gun. The legislation was named for James Brady, who was shot during an attempted assassination of President Ronald Reagan in 1981.

  • 1994: The Violent Crime Control and Law Enforcement Act

    The Violent Crime Control and Law Enforcement Act, signed into law by President Bill Clinton in 1994, instituted a ban on 19 kinds of assault weapons, including Uzis and AK-47s. The crime bill also banned the possession of magazines holding more than ten rounds of ammunition. (An exemption was made for weapons and magazines manufactured prior to the ban.)

  • 2004: Law Banning Magazines Holding More Than Ten Rounds Of Ammunition Expires

    In 2004, ten years after it first became law, Congress allowed a provision banning possession of magazines holding more than ten rounds of ammunition to expire through a sunset provision. Brady Campaign President Paul Helmke told HuffPost that the expiration of this provision meant that Rep. Gabby Giffords's alleged shooter was able to fire off 20-plus shots without reloading (under the former law he would have had only ten).

  • 2007: The U.S. Court of Appeals For The District Of Columbia Rules In Favor Of Dick Heller

    In 2007 The U.S. Court of Appeals for the District of Columbia ruled to allow Dick Heller, a licensed District police officer, to keep a handgun in his home in Washington, D.C. Following that ruling, the defendants petitioned the U.S. Supreme Court to hear the case.

  • 2008: The NICS Improvement Amendments Act

    Following the deadly shooting at Virginia Tech University, Congress passed legislation to require states provide data on mentally unsound individuals to the National Instant Criminal Background Check System, with the aim of halting gun purchases by the mentally ill, and others prohibited from possessing firearms. The bill was signed into law by President George W. Bush in January of 2008.

  • 2008: Supreme Court Strikes Down D.C. Handgun Ban As Unconstitutional

    In June of 2008, the United States Supreme Court upheld the verdict of a lower court ruling the D.C. handgun ban unconstitutional in the landmark case <em>District of Columbia v. Heller</em>.

  • Gabrielle Giffords And Trayvon Martin Shootings

    Gun control advocates had high hopes that reform efforts would have increased momentum in the wake of two tragic events that rocked the nation. In January of 2011, Jared Loughner opened fire at an event held by Rep. Gabrielle Giffords (D-Ariz.), killing six and injuring 13, including the congresswoman. Resulting attempts to push gun control legislation <a href="http://www.huffingtonpost.com/2012/04/09/trayvon-martin-shooting-gun-debate_n_1413115.html" target="_hplink">proved fruitless</a>, with neither proposal even succeeding in gaining a single GOP co-sponsor. More than a year after that shooting, Florida teenager Trayvon Martin was <a href="http://www.huffingtonpost.com/news/trayvon-martin" target="_hplink">gunned down</a> by George Zimmerman in an event that some believed would bring increased scrutiny on the nation's Stand Your Ground laws. While there has been increasing discussion over the nature of those statutes, lawmakers were <a href="http://www.huffingtonpost.com/2012/04/09/trayvon-martin-shooting-gun-debate_n_1413115.html" target="_hplink">quick to concede</a> that they had little faith the event would effectively spur gun control legislation, thanks largely to the National Rifle Association's vast lobbying power. Read more <a href="http://www.huffingtonpost.com/2012/04/09/trayvon-martin-shooting-gun-debate_n_1413115.html" target="_hplink">here</a>:

  • Colorado Movie Theater Shooting

    In July of 2012, a heavily armed gunman <a href="http://www.huffingtonpost.com/2012/07/20/aurora-shooting-movie-theater-batman_n_1688547.html" target="_hplink">opened fire on theatergoers</a> attending a midnight premiere of the final film of the latest Batman trilogy, killing 12 and wounding scores more. The suspect, James Eagan Holmes, allegedly carried out the act with a number of handguns, as well as an AR-15 assault rifle with a 100-round drum magazine. Some lawmakers used the incident, which took place in a state with some of the laxest gun control laws, to bring forth legislation designed to place increased regulations on access to such weapons, but many observers, citing previous experience, were <a href="http://www.huffingtonpost.com/2012/07/20/batman-shooting_n_1690547.html" target="_hplink">hesitant to say</a> that they would be able to overcome the power of the National Rifle Association and Washington gun lobby.

  • Sikh Temple Shooting

    On August 5, 2012, white supremacist Wade Michael Page opened fire on a Sikhs gathered at a temple in Oak Creek, Wis., killing six and wounding four more before turning the gun on himself.